@article{cda9497e32f24171a374e148d4b75cb4,
title = "Measurement of Z0 decays to hadrons, and a precise determination of the number of neutrino species",
abstract = "We have made a precise measurement of the cross section for e+e-→Z0→hadrons with the L3 detector at LEP, covering the s range from 88.28 to 95.04 GeV. From a fit to the Z0 mass, total width, and the hadronic cross section to be MZ 0=91.160 ± 0.024 (experiment) ±0.030(LEP) GeV, ΓZ 0=2.539±0.054 GeV, and σh(MZ 0)=29.5±0.7 nb. We also used the fit to the Z0 peak cross section and the width todetermine Γinvisible=0.548±0.029 GeV, which corresponds to 3.29±0.17 species of light neutrinos. The possibility of four or more neutrino flavors is thus ruled out at the 4σ confidence level.",
author = "{L3 Collaboration} and B. Adeva and O. Adriani and M. Aguilar-Benitez and H. Akbari and J. Alcaraz and A. Aloisio and G. Alverson and Alviggi, {M. G.} and Q. An and H. Anderhub and Anderson, {A. L.} and Andreev, {V. P.} and T. Angelov and L. Antonov and D. Antreasyan and A. Arefiev and T. Azemoon and T. Aziz and Baba, {P. V.K.S.} and P. Bagnaia and Bakken, {J. A.} and L. Baksay and Ball, {R. C.} and S. Banerjee and J. Bao and L. Barone and A. Bay and U. Becker and S. Beingessner and Bencze, {Gy L.} and J. Berdugo and P. Berges and B. Bertucci and Betev, {B. L.} and A. Biland and R. Bizzarri and Blaising, {J. J.} and P. Bl{\"o}meke and B. Blumenfeld and Bobbink, {G. J.} and M. Bocciolini and W. B{\"o}hlen and A. B{\"o}hm and T. B{\"o}hringer and B. Borgia and D. Bourilkov and M. Bourquin and D. Boutigny and Branson, {J. G.} and X. Leytens",
year = "1990",
month = mar,
day = "8",
doi = "10.1016/0370-2693(90)90476-M",
language = "English",
volume = "237",
pages = "136--146",
journal = "Physics Letters B",
issn = "0370-2693",
publisher = "Elsevier B.V.",
number = "1",
}